Q1 of 65 Page 10

In each of the following cases, let us justify & write whether the given values are the of the given quadratic equation:

x2 + x+1 = 0,1 and -1

We know that the roots of the quadratic equation satisfies the equation.

So, if 1 and -1 are the roots of


then they must satisfy the equation.


Therefore, putting 1 in the equation we have


= 12 + 1 + 1 = 1 + 1 + 1 = 3 which is not equal to 0.


So, it is not a root of the equation.


Putting -1 in the equation we have


= (-1)2 + (-1) + 1 = 1-1 + 1 = 1 which is not equal to 0.


So, it is also not a root of the equation.


Hence, 1 and -1 are not the roots of the equation.


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